And we showed you this amazing video yesterday's "play of the day." A close encounter with two divers were almost swallowed whole by humpback whales off the coast of california near l.A. The divers are speaking about their wild expedition. Abc's neal karlinsky has the story. Reporter: A picture-perfect day out off the california coast. Sean and francis were between scuba dives, snorkeling, hoping to get pictures of humpback whales in the distance, about a quarter mile away. I was trying to catch some flukes or tails or whatever. Reporter: But there are signs that trouble is coming. The whales are feeding. You see the tails breeching. Signs that it's meal time. And the sardines that they're chasing near the surface are trying to escape. They rushed the surface. And the first thing that came to mind, was there's a predator that's chasing them. The drivers are swarmed by the panicking sardines. They're right in the middle of a whale's dinner plate. Suddenly, these whales just popped up. Right out of the water ten feet from the boat. Reporter: Close call isn't a strong enough description. Stanback and antigua were feet from being swallowed alive. Humpback whales can weigh up to 40 tons and could easily swallow the diver's whole. Marine biologists say they're not interested in people. But accidents have happened before. What happened there, that's like getting struck by lightning. It's a 1 in a million chance. Reporter: The whales did not miss a beat and could be seen chasing their dinner back out to sea. A whale of a story no one would believe if they didn't have the video to prove it. It would be a whale tale without the evidence. Reporter: For "good morning america," neal karlinsky, abc news, los angeles. Sam was filling us in -- they open their mouths. They take in everything. And they filter out the water and swallow the tasty morsels. You will be a tasty morsel. And you can hear the panicking sardines, get out of the way. Exactly. Really. I learn so much.

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